(() => {
    //布尔类型
    let flag = true;
    flag = false;
    console.log(flag); //false
    //flag = 1;//报错
    //数字
    let a1 = 10; // 十进制
    let a2 = 0b1010; // 二进制
    let a3 = 0o12; // 八进制
    let a4 = 0xa; // 十六进制
    console.log(a1, a2, a3, a4); //10 10 10 10
    //字符串和数字之间能够一起拼接
    let str = "我考了";
    let num = 100;
    console.log(str + num); //我考了100
    let und = undefined;
    let nll = null;
    console.log(und, nll); //undefined null
    let arr1 = [1, 2, 3, 4];
    let arr2 = [5, 6, 7, 8];
    console.log(arr1, arr2);
    let Color;
    (function (Color) {
        Color[Color["Red"] = 0] = "Red";
        Color[Color["Green"] = 1] = "Green";
        Color[Color["Blue"] = 2] = "Blue";
    })(Color || (Color = {}));
    let myColor = Color.Red;
    console.log(myColor, Color.Green, Color.Blue);
    let Color2;
    (function (Color2) {
        Color2[Color2["Red"] = 1] = "Red";
        Color2[Color2["Green"] = 3] = "Green";
        Color2[Color2["Blue"] = 4] = "Blue";
    })(Color2 || (Color2 = {}));
    let c = Color2.Red;
    console.log(c, Color2.Green, Color2.Blue);
    function fn() {
        console.log('fn()');
        // return undefined
        // return null
        //Freturn 1 // error
    }
    fn();
})();
